10 Tips on How to Make Windows More Energy Efficient

If sitting by the window means you need to bundle up under the blankets or crank up the heat, then your windows aren’t doing their job well. But don’t worry—there are plenty of simple ways to increase the insulation power of your home’s windows. Even better? Several of them are DIY-friendly. Check out these 10 tips to learn how to make your windows more energy efficient and start saving on your energy bills.

1. Replace Your Old Windows

Replacing your windows is the most effective (and, as you might expect, expensive) way to increase their energy efficiency. Window technology has improved over the years, and considering that windows typically last between 15 and 50 years, it could make sense to upgrade to newer, more energy-efficient models if yours are more than a couple of decades old.

Average window replacement costs vary, but the typical range is between $200 and $1,200 per window, with an installation cost of $200 to $400 per window. That brings your total cost per window to an average of $800.

If you want to add energy-efficient windows, however, prices start to climb. On average, energy-efficient windows cost $400 to $1,800 per window, plus an extra $200 to $400 per window for installation. That’s a total of around $1,200 per window. You can opt for highly efficiency windows that have triple-pane glass and low-emissivity (low-E) coatings as well, which could increase your cost even more.

2. Apply Window Caulk and Weatherstrips to Prevent Air Leaks

Hot and cold air can enter your home through spaces between the glass, window sash, and window frame. Caulking and weatherstripping, however, are inexpensive and easy solutions to make old windows more energy-efficient. The U.S. Department of Energy states that you can save as much as 5% to 10% on your energy bills by ensuring your home is properly weatherstripped and caulked.

If the areas near your windows feel drafty, you’ll likely need to seal them. Many types of caulking and weatherstripping materials are long-lasting—some can last anywhere from five to 20 years—but you should still check them annually to provide the best weather protection.

Apply weatherstripping to areas that can handle friction and weather changes, and apply caulk on the sides and joints of your window frame and other window areas that are stationary. If the gaps are larger, you can fill them with spray foam insulation.

3. Install Window Inserts

Installing window inserts is an easy way to make single-pane windows more energy efficient—without ripping them out or adding external accessories, like awnings or blinds.

Window inserts are framed panes of glass, usually with tubing around the edges, that pop into the inside of your existing window frame. It should only take a couple of minutes to install a window insert. After you finish, you’ll instantly have another layer of protection between the interior and exterior of your home.

Depending on the shape of your window, you can either buy a custom-sized or standard-sized window insert. Not only can window inserts increase the energy efficiency of your windows, but they can also decrease outdoor noise and improve insulation.

4. Install Awnings to Block the Sun

The U.S. Department of Energy reports that awnings on southern-facing windows reduce the amount of solar heat gain in your home by as much as 65% in the summer. Awnings used on western-facing windows can reduce it by up to 77%. Installing a retractable awning means you can benefit from the warmth of the sun in the winter and protect yourself from solar heat gain in the summer, which is a win-win situation.

You can either install individual awnings over single windows or install an awning that covers a larger portion of your home to avoid individual installations. Awnings that also cover exterior walls can reduce their solar heat gain as well.

You should opt for long-lasting materials, like synthetic fabrics, which resist mildew and fading. If you’re not sure which option and sizing would lead to the most savings, find a local awning installer to help you determine the best, money-saving solutions.

5. Add Blinds, Shades, and Draperies to Block Drafts and Sunlight

Whether you prefer blinds, shades, or draperies in your home, one thing’s for sure—all can improve your window’s energy efficiency. Combining draperies and either blinds or shades maximizes the prevention of heat loss in the winter and sun protection in the summer. Not to mention, you can open all of these options to let sunlight in for warmth when it’s cold and close it up if it’s too hot outside.

Custom window treatments cost more, but a tighter fit inside or over your window will mean better protection from the outdoor air.

Let’s take a look at each option and how much window-blocking installations can save you.

Window Draperies

Drapes don’t just offer your home a pop of color and regality—insulated draperies can improve a window's energy efficiency in both the summer and winter. The thermal insulation can reduce cold drafts from coming in and reduce heat loss by as much as 10% while also preventing heat from entering your home by 33% if you use a drapery with white-plastic backings. 

Window Blinds

Window blinds are also a good choice for reducing heat gained from the sun. Quality blinds can reduce the heat by up to 45%. Blinds are not as effective for reducing heat loss in the winter, though, as they tend not to be very insulative.

Insulated Cellular Shades

For homes that have colder winters, cellular shades are a better option because they can reduce heat loss by 40% when it’s cold outside. On top of that, these types of shades can reduce solar heat gain in the winter by 60%. You can easily pull cellular shades up or down and have them custom-fitted to your windows for a clean look and maximum efficiency.

6. Apply Solar Window Film to the Glass

Solar window film is like a car sun-shield, only it’s for your home instead. This film blocks up to 35% of solar heat and 95% to 99.9% of UV rays from heating your home on a hot summer day. 

Window films can be permanent or temporary. Temporary film treatments are the best choice if you live in an area with cold winters because you can benefit from the sun warming your home during the cold season, and you might want to remove them once it starts to get cold. A permanent film—usually called window tinting—is a better option for areas that are warmer all year, but keep in mind that most window films will reduce visibility.

You can DIY a window film installation or have it done professionally by a local window replacement pro. The film costs around $8 to $15 per square foot for the materials alone. A pro knows how to measure the film and reduce air bubbles, thus improving the efficacy of the film and the look of your interior, so it’s a good idea to call in an expert.

7. Put Up Low-Emissivity Storm Panels

Low-emissivity (low-E) storm windows are extra glass panes that are installed over your existing windows to help insulate and conserve indoor heat in the winter and reflect outdoor radiant heat in the summer. As such, these windows can save you about as much money as new, double-pane windows. The best part is that they’ll also cost you around 60% less than new windows while saving you anywhere from 10% to 30% on your heating and cooling expenses.

Low-E windows are more of a permanent solution than many other energy-efficiency upgrades. For example, when comparing low-E vs. window film, the former outperforms the latter in multiple categories, including energy efficiency, appearance, and long-term reliability.

Note that the efficiency of storm panels is largely dependent on the condition of your current window setup; if your windows need some TLC, installing panels can only do so much. Also, since storm panels are manufactured from many materials, including plastic or polyethylene, not all panels provide the best visibility, so talk with a pro before you make a purchase.

8. Hang Exterior Shutters

Exterior shutters don't require space on the inside of your home. Most are made from fabric, wood, aluminum, or steel, and they work by blocking out solar heat, making them ideal for homes in hotter climates. You'll need to make sure your shutters are measured and installed properly to ensure they fit and work correctly.

You might also want to consider shutter styles that protect against heavy winds, depending on where you live. You can operate the opening and closing system from the inside of your home or via remote control.

9. Upgrade or Repair Your Window Frames

Wood window frames, especially, are prone to decay and damage over time, making it important that you inspect your window frames regularly for signs of wear. A pesky, old window frame can lead to air seepage that makes for much higher energy bills, even if you don’t have gaps around the wall opening. As such, you’ll want to repair or replace window frames as soon as possible if there is a problem.

Fiberglass and clad wood frames have the highest r-value and are the most energy-efficient window frame materials, while aluminum and vinyl are less efficient. Wood frames fall somewhere in the middle.

While you’re replacing your windows, you may want to ask an insulation company near you to install blown-in insulation around the frame while it’s exposed. Blown-in insulation can help decrease drafts coming in through the wall cavity around your window, especially if the existing insulation is older or inefficient. If you’re working with a skylight, you could opt for roof insulation instead.

10. Have a Home Energy Audit

Troubleshooting the cause of your window’s energy inefficiency can feel a little like taking a wild stab in the dark if you’re not experienced in improving your home’s energy efficiency. In this case, you’ll want to hire a local home energy auditor to evaluate your windows and other areas of the home to best conserve energy and save money. 

A home energy audit costs just over $400 on average, but low-income families may qualify for a free audit, and some state and local governments might offer rebates to offset the expenses for anyone ineligible for a free audit. And, of course, you’ll end up saving in the long run. According to the U.S. Department of Energy, reducing drafts in your home can save you between 5% to 30% yearly on your energy bills, so it pays to boost your efficiency.

The Bottom Line

Some windows are just too old for these energy-efficient tricks to be effective. If you’ve tried everything but replacing your windows and still have higher energy bills than you’d like, it might be time to take the plunge and work with a local window installer to upgrade your windows.

When choosing the best replacement windows, look for ENERGY STAR®-qualified windows, which are designed with energy efficiency in mind. Upgrade to a more insulative frame material, like fiberglass, choose double-pane glass at the very least, and consider triple-pane glass for maximum efficiency. Additionally, have a professional install your window to ensure the wall opening is properly sealed and insulated for the best results.